Method for manufacturing a trigger element of a sear mechanism for a firearm

ABSTRACT

A sear mechanism for a firearm includes a trigger element having one or more contact surfaces on which one or more movable or pivotable components of the sear mechanism selectively contacts or slides. In some embodiments, the trigger element is made by producing an intermediate workpiece of the trigger element by a manufacturing process, and electric discharge machining the intermediate workpiece of the trigger element to provide the contact surfaces.

CROSS-REFRENCE TO RELATED APPLICATION(S)

This application is a continuation-in-part of U.S. Ser. No. 29/500,695,filed on Aug. 27, 2014, entitled COMPONENT OF A TRIGGER MECHANISM FOR AFIREARM, the disclosure of which is incorporated herein by reference inits entirety.

BACKGROUND

A trigger mechanism actuates the firing sequence of a firearm. Thetrigger mechanism typically includes a lever or button actuated by theindex finger. In addition, the trigger mechanism includes severalmechanical components that engage and interact with each other toactuate a firing mechanism of the firearm.

The operation of the trigger mechanism has an impact on the shootingaccuracy of a firearm. Accuracy can be reduced if too much force isrequired to pull back the trigger. Additionally, a rough, uneven, orunpredictable hammer release point can also result in reduced accuracyand may lead to frustration with or distrust of a firearm.

SUMMARY

In general terms, this disclosure is directed to a sear mechanism for afirearm. In one possible configuration and by non-limiting example, thesear mechanism includes a trigger element having one or more contactsurfaces on which one or more movable or pivotable components of thesear mechanism contacts or slides. In some embodiments, the contactsurfaces are made using an electric discharge machining process. Variousaspects are described in this disclosure, which include, but are notlimited to, the following aspects.

In one aspect, a method for manufacturing a trigger element of a searmechanism for a firearm is provided. The method may include producing anintermediate workpiece of the trigger element by a manufacturingprocess; and electric discharge machining the intermediate workpiece ofthe trigger element to provide at least one contact surface onto whichat least one pivotable element of the sear mechanism selectivelycontacts.

In another aspect, a sear mechanism for a firearm is provided. The searmechanism may include a housing configured to be detachably mounted inthe firearm; a trigger element pivotally connected to the housing andconnected to a trigger through a trigger rod, the trigger rod disposedwithin the firearm, the trigger element comprising: a trigger biasingmechanism configured to bias the trigger element relative to thehousing; a trigger sear including a sear contact surface produced byelectric discharge machining; the disconnector pad including adisconnector contact surface produced by electric discharge machining; adisconnector element disposed in the housing and pivotally connected toat least one of the housing and the trigger element, the disconnectorelement comprising: a trigger element contact portion arranged at afirst end of the disconnector element and configured to selectivelycontact the disconnector pad of the trigger element; a hammer searcontact face arranged at a second end of the disconnector element; and adisconnector biasing mechanism configured to bias the disconnectorelement relative to the trigger element such that the trigger elementcontact portion is biased to contact the disconnector pad; a hammerelement disposed in the housing and configured to pivot between a cockedposition and a released position, the hammer element comprising: ahammer biasing mechanism configured to bias the hammer element to thereleased position; and a hammer sear having a first sear edge and asecond sear edge, the first sear edge configured to be selectivelycontact the sear contact surface of the trigger sear and engaged withthe trigger sear in the cocked position, and the second sear edgeconfigured to selectively contact the hammer sear contact face of thedisconnector element, wherein at least one of the trigger element andthe disconnector element is configured to pivot against resistance of atleast one of the trigger biasing mechanism and the disconnector biasingmechanism as the trigger is pulled, and wherein the first sear edge ofthe hammer sear is engaged to the trigger sear of the trigger element inthe cocked position, and is released from the trigger sear of thetrigger element in the released position to cause the hammer element torotate by force of the hammer biasing mechanism and strike a firing pinof the firearm.

In yet another aspect, a trigger element for production of a searmechanism for a firearm is provided. The trigger element produced by aprocess including: producing an intermediate workpiece of the triggerelement by a manufacturing process; and electric discharge machining theintermediate workpiece of the trigger element to provide at least onecontact surface onto which at least one pivotable element of the searmechanism selectively contacts.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic side view of an example firearm.

FIG. 2A is a schematic view of an example trigger mechanism illustratingan example sear mechanism in a cocked position.

FIG. 2B is a schematic view of the trigger mechanism of FIG. 2Aillustrating the sear mechanism in a released position.

FIG. 3 is a perspective view of an example sear mechanism.

FIG. 4 is an exploded view of the sear mechanism of FIG. 3.

FIG. 5 is a schematic view of an example housing of the sear mechanismof FIG. 4.

FIG. 6 is a schematic view of an example hammer element of the searmechanism of FIG. 4.

FIG. 7 is a perspective view of an example disconnector element of thesear mechanism of FIG. 4.

FIG. 8 is a perspective view of an example trigger element of the searmechanism of FIG. 4.

FIG. 9 is a side cross-sectional view of the sear mechanism illustratingthe assembly of the sear mechanism.

FIG. 10A illustrates that the sear mechanism is in a cocked position.

FIG. 10B illustrates that the sear mechanism is in an intermediateposition.

FIG. 10C illustrates that the sear mechanism is at a release point.

FIG. 10D illustrates that the sear mechanism is in a released position.

FIG. 11 is another perspective view of the trigger element of FIG. 8.

FIG. 12 is a front view of the trigger element of FIG. 8.

FIG. 13 is a rear view of the trigger element of FIG. 8.

FIG. 14 illustrates an example method of manufacturing the triggerelement.

FIG. 15A is a side view of an example intermediate workpiece.

FIG. 15B is a perspective view of the intermediate workpiece of FIG.15A.

FIG. 16 illustrates an example method of performing an operation of FIG.14.

FIG. 17 illustrates an example method of performing an operation of FIG.16.

FIG. 18 schematically illustrates the method of FIG. 17.

FIG. 19 illustrates an example method of performing an operation of FIG.16.

FIG. 20 schematically illustrates the method of FIG. 19.

FIG. 21 illustrates an example method of performing an operation of FIG.16.

FIG. 22 schematically illustrates the method of FIG. 20.

DETAILED DESCRIPTION

Various embodiments will be described in detail with reference to thedrawings, wherein like reference numerals represent like parts andassemblies throughout the several views. Reference to variousembodiments does not limit the scope of the claims attached hereto.Additionally, any examples set forth in this specification are notintended to be limiting and merely set forth some of the many possibleembodiments for the appended claims.

FIG. 1 is a schematic side view of an example firearm 100. The firearm100 generally includes a receiver body 102, a barrel assembly 104, arail assembly 106, a foregrip 108, a trigger 110, a pistol grip 112, amagazine 114, a safety assembly 116, a butt assembly 118, a searmechanism 120, a sear locking mechanism 122, and a bolt carrier stoplever 124.

The firearm 100 can be of a variety of types. Examples of the firearm100 include handguns, rifles, shotguns, carbines, personal defenseweapons, semi-automatic rifles, and assault rifles. In at least oneembodiment, the firearm 100 is the “Tavor Assault Rifle—21st Century”(“TAR-21” or simply Tavor) by Israel Military Industries, or one of itsvariants, such as GTAR-21, CTAR-21, STAR-21, Micro TAR-21 (X95),Zittara, Semi-automatic TC-21, 7.62 NATO X95, 5.45 Russian X95, andTavor SAR.

The receiver body 102 is configured to house a firing mechanism andassociated components as found in, for example, Tavor type rifles andtheir variants. The firing mechanism typically includes a triggermechanism 140 including the sear mechanism 120, which is described andillustrated in more detail with reference to FIG. 2. Further, thereceiver body 102 defines an internal cavity configured to receive abolt assembly 142 (FIG. 2). The bolt assembly 142 is slidably disposedin the cavity for axially reciprocating recoil movement therein.

The barrel assembly 104 is configured to be installed to the receiverbody 102 and operates to provide a path to release an explosion gas andpropel a projectile therethrough.

The rail assembly 106 is installed to the receiver body 102 to allowattachment of a variety of accessory, such as laser or telescopicsights, scopes, tactical lights, laser aiming modules, bipods, bayonets,rifle optics, and other accessories.

The foregrip 108 provides a mechanism held by the shooter's hand,including when operating the trigger 110. For example, a user can firmlyposition the butt 118 to his or her shoulder with one hand on theforegrip 108 and the other hand on the pistol grip 112 to be ready forpulling the trigger 110 with the trigger finger.

The trigger 110 is a lever pulled by the finger of the shooter (e.g.,the index finger) to actuate the firing mechanism of the firearm 100.The trigger 110 is associated with the trigger mechanism 140 asdescribed in FIG. 2.

The pistol grip 112 is a portion of the firearm 100 that is held by thehand and orients the hand in a forward, vertical orientation to operatethe trigger 110.

The magazine 114 is an ammunition storage and feeding device within thefirearm 100. In at least one embodiment, the magazine 114 is detachablyinstalled to the firearm 100. For example, the magazine 114 is removablyinserted into a magazine well of the receiver body 102 of the firearm100.

The safety assembly 116 is a mechanism for preventing the accidentaldischarge of the firearm 100, helping to ensure safe handling. In atleast one embodiment, the safety assembly 116 includes a safety leverthat is switchable between two or more positions, such as a fireposition and a safe position. The movement of the safety lever can betransferred rearward to the sear mechanism 120 with the aid of a triggerrod 144 (FIG. 2) disposed in the side of the receiver body 102.

The butt assembly 118 provides a butt for a shooter to firmly supportthe firearm 100 and easily aim it by holding the butt against his or hershoulder when firing. In at least one embodiment, the butt assembly 118includes a butt cover that is hinged to the receiver body 102 so as toselectively open the receiver body 102. The butt cover can be secured tothe receiver body 102 with a butt locking pin that is configured to beinserted to a first pin receiving hole on one side of the receiver body102 and pass through corresponding butt locking holes until a second pinreceiving hole on the other side of the receiver body 102. When the buttcover is open, several components of the firearm 100 can be inserted tothe interior of the receiver body 102, such as the bolt assembly 142 anda recoil mechanism.

The sear mechanism 120 constitutes the trigger mechanism 140 (FIG. 2)with the trigger 110 and holds several components (such as a hammer, astriker, and a bolt) configured to discharge the firearm when apredetermined amount of pressure or force is applied to the trigger 110.As described herein, the sear mechanism 120 is designed to replace theOEM sear mechanism of the firearm 100, such as Tavor type rifles, andprovide smooth, consistent pulling actions of the trigger 110, therebyimproving accuracy in shooting.

The sear mechanism 120 is replaceably installed to the receiver body102. As illustrated in FIG. 1, the sear mechanism 120 is configured tobe inserted into the interior of the receiver body 102 and fixed to thereceiver body 102 with the sear locking mechanism 122.

The sear locking mechanism 122 is configured to secure the searmechanism 120 in place within the receiver body 102. In at least oneembodiment, the sear locking mechanism 122 includes one or more searmechanism locking pins 126 and one or more corresponding receiving holes128 provided on both sides of the receiver body 102. The sear mechanismlocking pins 126 are respectively inserted to one of the correspondingreceiving holes 128 on one side of the receiver body 102, pass throughmounting holes 238 or 240 (FIG. 5) of the sear mechanism 120, and engagethe other of the corresponding receiving holes 128 on the other side ofthe receiver body 102.

The bolt carrier stop lever 124 is configured to open the receiver body102 and make the interior of the receiver body 102 accessible for thesear mechanism 120 to be inserted therein. As depicted in FIG. 1, thebolt carrier stop lever 124 is pivotally connected to the receiver body102 such that the lever 124 hinges on the receiver body 102.

Other embodiments of the firearm 100 have other configurations than theexamples illustrated and described with reference to FIG. 1. Forexample, some of the components listed above are not included in somealternative embodiments.

FIG. 2 illustrates an example operation of the trigger mechanism 140including the sear mechanism 120. In particular, FIG. 2A is a schematicview of the trigger mechanism 140 illustrating the sear mechanism 120 ina cocked position. FIG. 2B is a schematic view of the trigger mechanism140 illustrating the sear mechanism 120 in a released position. Thetrigger mechanism 140 operates to actuate the bolt assembly 142. Inaddition to the trigger 110 and the sear mechanism 120, the triggermechanism 140 includes a trigger rod 144.

The trigger mechanism 140 is configured to actuate the firing sequenceof the firearm 100 by operating the bolt assembly 142 accommodated inthe receiver body 102.

The bolt assembly 142 operates to block the rear of a chamber while apropellant burns and allow another cartridge or shell to be insertedinto the chamber for the next firing. In at least one embodiment, thebolt assembly 142 is propelled in a rearward direction by recoil orexpanding gas and returns in a forward direction by a recoil mechanism.When it moves rearward, an extractor pulls the spent casing from thechamber, and when it moves forward, it strips a cartridge from themagazine and pushes it into the chamber.

The trigger rod 144 is disposed in the receiver body 102 (shown inFIG. 1) to operatively connect the trigger 110 and the sear mechanism120. The trigger rod 144 pivotally engages the trigger 110 at a firstrod end 146, and is connected to one or more components (e.g., a triggerelement 208, as discussed herein) of the sear mechanism 120 at a secondrod end 148. In at least one embodiment, when the trigger 110 is pulled,the movement of the trigger 110 is transferred to the sear mechanism 120through the trigger rod 144 such that the sear mechanism 120 is actuatedfrom the cocked position (FIG. 2A) to the released position (FIG. 2B).

As described herein, the sear mechanism 120 includes a spring-biasedhammer (e.g., a hammer element 204 (FIG. 5)) that is cocked in thecocked position (FIG. 2A) and then released by a sear component (e.g., atrigger element 208 (FIG. 5)) that is actuated by the trigger 110through the trigger rod 144. The hammer strikes a firing pin carried bythe bolt assembly 142, which in turn is thrust forward to contact anddischarge a cartridge loaded in a chamber. A portion of the expandingcombustion gases traveling down the barrel assembly 104 is used to drivethe bolt assembly 142 rearward against a forward biasing force of arecoil spring for automatically ejecting the spent cartridge casing andautomatically loading a new cartridge into the chamber from the magazine114 when the bolt assembly 142 returns forward.

FIG. 3 is a perspective view of an example sear mechanism 120. In thedepicted example, the sear mechanism 120 is in the cocked position. Asdescribed, the sear mechanism 120 is part of the trigger mechanism 140(shown in FIG. 2) and actuated by the trigger 110 via the trigger rod144. The sear mechanism 120 operates to discharge the firearm 100 when apredetermined amount of force is applied to pull the trigger 110.

The sear mechanism 120 is configured to increase the controllability fora shooter when the firearm 100 is used and improve the accuracypotential of the shooter, such as by minimizing mechanical distractionswhich can hinder accurate control of the firearm 100.

In at least one embodiment, the sear mechanism 120 is configured toprovide a two-stage trigger mechanism that allows for a smooth firststage and a light, crisp second stage which causes the firearm 100 to bedischarged once the resistance is overcome. The sear mechanism 120according to the present disclosure can provide a two-stage triggermechanism which has a consistent, reliable trigger pull.

As described herein, one or more of the pivotable elements (e.g., atrigger element) of the sear mechanism 120 include one or more contactsurfaces on which one or more of the other pivotable or movable elementsof the sear mechanism can selectively contact or slide. The searmechanism 120 is operated by the interactions between the movable orpivotable elements of the sear mechanism. The interactions can includeflat surface-to-surface contacts between the elements of the searmechanism. However, such flat surface-to-surface contacts are extremelydifficult to achieve as any deviation from perfect component size cancause two abutting surfaces to not sit flat to each other, therebynegatively affecting the sear or contact engagement and the trigger pullweight. Therefore, the accurate dimension and smoothness of the contactsurfaces in the sear mechanism is important to make a trigger mechanismlight, smooth, and reliable.

FIG. 4 is an exploded view of the sear mechanism 120 of FIG. 3. In atleast one embodiment, the sear mechanism 120 includes a housing 202, ahammer element 204, a disconnector element 206, and a trigger element208.

The housing 202 provides a space for operatively mounting the hammerelement 204, the disconnector element 206, and the trigger element 208.The housing 202 is configured to be detachably mounted into an openingprovided in the receiver body 102 of the firearm 100. An example of thehousing 202 is described and illustrated in more detail with referenceto FIG. 5.

The hammer element 204 is disposed in the housing 202 and configured topivot between the cocked position and the released position such thatthe hammer element 204 strikes a firing pin of the bolt assembly 142 asit moves from the cocked position to the released position. An exampleof the hammer element 204 is described and illustrated in more detailwith reference to FIG. 6.

The disconnector element 206 is disposed in the housing 202 andpivotally connected to at least one of the housing 202 and the hammerelement 204. The disconnector element 206 interacts with the hammerelement 204 and the trigger element 208 to operate the hammer element204 between the cocked position and the released position and providethe two-stage trigger movement. An example of the disconnector element206 is described and illustrated in more detail with reference to FIG.7.

The trigger element 208 is pivotally connected to the housing 202 andconnected to the trigger 110 through the trigger rod 144. The triggerelement 208 is configured to interact with the hammer element 204 andthe disconnector element 206 to operate the hammer element 204 betweenthe cocked position and the released position. The trigger element 208is configured to accurately position the disconnector element 206 inrelation to the hammer element 204 and provide the two-stage triggermovement. An example of the trigger element 208 is described andillustrated in more detail with reference to FIG. 8.

With continued reference to FIG. 4, the sear mechanism 120 includes anoperating mechanism for operatively connecting the hammer element 204,the disconnector element 206, and the trigger element 208 to the housing202. In at least one embodiment, the operating mechanism includes afirst pivot support 212, a second pivot support 214, a stopper pin 216,a trigger biasing support 218, a trigger biasing member 220, adisconnector biasing support 222, a disconnector biasing member 224, ahammer biasing member 226, a first pivot support pin 228, and a secondpivot support pin 230.

The first pivot support 212 is configured to pivotally support thehammer element 204 in the housing 202. In at least one embodiment, thefirst pivot support 212 is configured as a pivot pin that is insertedinto, and supported by, the housing 202 so as to be arranged across theopposing side walls of the housing 202. As described herein, the firstpivot support 212 engages the hammer element 204 and is rotatablysupported by the opposing side walls of the housing 202. In otherembodiments, the second pivot support 214 is fixedly supported by thehousing 202 and provides a surface on which the hammer element 204 bearsand pivots.

The second pivot support 214 is configured to pivotally support thetrigger element 208 and the disconnector element 206 in the housing 202.In at least one embodiment, the second pivot support 214 is configuredas a pivot pin that is inserted into, and supported by, the housing 202so as to be arranged across opposing side walls of the housing 202. Asdescribed herein, the second pivot support 214 engages the triggerelement 208 and the disconnector element 206 and is rotatably supportedby the opposing side walls of the housing 202. In other embodiments, thesecond pivot support 214 is fixedly supported by the housing 202 andprovides a surface on which the trigger element 208 and the disconnectorelement 206 bear and pivot.

The stopper pin 216 provides a stop that terminates downward movement ofthe hammer element 204 during the recoil process.

The trigger biasing support 218 is configured to provide a support orguide for the trigger biasing member 220. The trigger biasing support218 can be fixed on the inner base surface of the housing 202 and extendtherefrom such that the trigger biasing member 220 is placed to surroundat least a portion of the trigger biasing support 218. The triggerbiasing support 218 holds the trigger biasing member 220 in place as thetrigger biasing member 220 acts against the trigger element 208. Inother embodiments, the trigger biasing support 218 is integrally formedwith either the housing 202 or the trigger element 208.

The trigger biasing member 220 is configured to bias the trigger element208 relative to the housing 202. In at least one embodiment, the triggerbiasing member 220 is configured as a coil compression spring. Thetrigger biasing member 220 is arranged between the trigger element 208and the inner base surface of the housing 202.

The disconnector biasing support 222 is configured to support thedisconnector biasing member 224. The disconnector biasing support 222can be fixed on the disconnector element 206 and extend therefrom suchthat the disconnector biasing member 224 is placed to surround thedisconnector biasing support 222. The disconnector biasing support 222holds the disconnector biasing member 224 in place as the disconnectorbiasing member 224 operates between the disconnector element 206 and thetrigger element 208. In other embodiments, the disconnector biasingsupport 222 is integrally formed with the disconnector element 206.

The disconnector biasing member 224 is configured to bias thedisconnector element 206 relative to the trigger element 208. In atleast one embodiment, the disconnector biasing member 224 is configuredas a coil compression spring. The disconnector biasing member 224 can bearranged between the disconnector element 206 and the trigger element208.

The hammer biasing member 226 is configured to bias the hammer element204 to the released position relative to the housing 202. In at leastone embodiment, the hammer biasing member 226 is configured as a torsionspring that works by torsion or twisting. When the spring is twisted, itexerts a torque in the opposite directions, proportional to the amountit is twisted. The hammer biasing member 226 can have a coil portion, afirst leg, and a second leg opposite to the first leg. The first leg ofthe hammer biasing member 226 can engage a portion of the hammer element204 while the second leg of the hammer biasing member 226 abuts aportion of the housing 202. The hammer biasing member 226 biases thehammer element 204 toward the released position. When the hammer element204 is in the cocked position, the hammer biasing member 226 is bentsuch that the first and second legs come closer against the biasingforce thereof.

The first pivot support pin 228 is used to fix the hammer element 204with the first pivot support 212. In at least one embodiment, the firstpivot support pin 228 is inserted into a fixing pin insert hole 260(FIG. 6) of the hammer element 204 and subsequently into a fixing pinreceptacle 213 of the first pivot support 212. As such, the hammerelement 204 is fixedly attached to the first pivot support 212 such thatthe hammer element 204 pivots as the first pivot support 212 rotatesrelative to the housing 202.

The second pivot support pin 230 is used to fix the disconnector element206 with the second pivot support 214 and enable the trigger element 208to pivot on the second pivot support 214. In at least one embodiment,the second pivot support pin 230 is inserted into a fixing pin inserthole 280 (FIG. 7) of the disconnector element 206 and subsequently intoa fixing pin receptacle 215 of the second pivot support 214. As such,the disconnector element 206 is fixedly attached to the second pivotsupport 214 such that the disconnector element 206 pivots as the secondpivot support 214 rotates relative to the housing 202. As describedherein, the disconnector element 206 is rotatably engaged with thetrigger element 208 through the second pivot support 214. For doing so,first and second pivot support insert holes 300 and 302 (FIG. 8) of thetrigger element 208 are aligned with a pivot support insert hole 278(FIG. 7) of the disconnector element 206, and the second pivot support214 is inserted into the first and second pivot support insert holes 300and 302 of the trigger element 208 and the pivot support insert hole 278of the disconnector element 206 to pivotally hold the trigger element208 relative to the housing 202 and the disconnector element 206.

FIG. 5 is a schematic view of the housing 202 of FIG. 4. In at least oneembodiment, the housing 202 includes first and second side walls 232 and234, a bore 236, one or more first mounting holes 238, one or moresecond mounting holes 240, support openings 242A and 242B for supportingthe hammer element 204, support openings 244A and 244B for supportingthe disconnector element 206 and the trigger element 208, and stoppersupport openings 246A and 246B.

The first and second side walls 232 and 234 extend between a firsthousing end 235 and a second housing end 237. The first and second sidewalls 232 and 234 constitute at least part of the housing 202 and definethe bore 236.

The bore 236 is defined at least partially by the first and second sidewalls 232 and 234 and configured to provide a space for receiving thecomponents of the sear mechanism 120, such as the hammer element 204,the disconnector element 206, the trigger element 208, and otherassociated elements.

The first mounting holes 238 are provided to the housing 202 to couplethe sear mechanism 120 to the firearm 100 when the sear mechanism 120 isinserted into the firearm 100, as shown in FIG. 1. In the depictedembodiment, two first mounting holes 238 are provided with one extendingfrom the first side wall 232 and the other extending from the secondside wall 234. When the sear mechanism 120 is inserted into the receiverbody 102 of the firearm 100 and the first mounting holes 238 are alignedwith the corresponding first receiving holes 128A of the receiver body102, a first locking pin 126A is inserted into one of the firstreceiving holes 128A, the first mounting holes 238, and the other of thefirst receiving holes 128A to couple the sear mechanism 120 to thereceiver body 102.

The second mounting holes 240 are similarly provided to the housing 202couple the sear mechanism to the firearm 100 in cooperation with thefirst mounting holes 238. In the depicted embodiment, two secondmounting holes 240 are provided with one extending from the first sidewall 232 and the other extending from the second side wall 234. When thesear mechanism 120 is inserted into the receiver body 102 of the firearm100 and the second mounting holes 240 are aligned with the correspondingsecond receiving holes 128B of the receiver body 102, a second lockingpin 126B is inserted into one of the second receiving holes 128B, thesecond mounting holes 240, and the other of the second receiving holes128B to couple the sear mechanism 120 to the receiver body 102.

The support openings 242A and 242B are used to rotatably support thefirst pivot support 212. In the depicted embodiment, a first supportopening 242A is formed on the first side wall 232, and a second supportopening 242B is correspondingly formed on the second side wall 234. Thefirst pivot support 212 is first inserted to one of the support openings242A and 242B and then to the other of the support openings 242A and242B after passing through the hammer element 204. The support openings242A and 242B rotatably support both ends of the first pivot support212, respectively.

The support openings 244A and 244B are used to rotatably support thesecond pivot support 214. In the depicted embodiment, a first supportopening 244A is formed on the first side wall 232, and a second supportopening 244B is correspondingly formed on the second side wall 234. Thesecond pivot support 214 is first inserted to one of the supportopenings 244A and 244B, and then to the other of the support openings244A and 244B after passing through the trigger element 208 and thedisconnector element 206. The support openings 244A and 244B rotatablysupport both ends of the second pivot support 214, respectively.

The stopper support openings 246A and 246B support the stopper pin 216therein, as shown in FIG. 4.

FIG. 6 is a schematic view of the hammer element 204 of FIG. 4. In atleast one embodiment, the hammer element 204 includes a hammer body 250,a hammer head 252, and a hammer tail 254 including a biasing membersupport portion 256, a pivot support insert hole 258, a fixing pininsert hole 260, and a notch portion 262. The hammer element 204 furtherincludes a hammer leg 264 and a hammer sear 266 with a first sear edge268 and a second sear edge 270.

The hammer body 250 extends between the hammer head 252 and the hammertail 254 and is configured to swing on the hammer tail 254 between thecocked position and the released position. The hammer body 250 is usedto hold one end of the hammer biasing member 226, such as a torsionspring while the other end of the hammer biasing member 226 abuts thehousing 202.

The hammer head 252 is configured to selectively engage the boltassembly 142 (e.g., the firing pin thereof) when the hammer element 204is in the released position. The hammer head 252 can have differentshapes to engage the corresponding portion of the bolt assembly 142.

The hammer tail 254 is configured to engage the first pivot support 212and operates as a pivot axis A1 of the hammer element 204.

The biasing member support portion 256 of the hammer tail 254 isconfigured to engage the coil portion of the hammer biasing member 226.In the depicted embodiment, the biasing member support portion 256extends perpendicularly to a length of the hammer body 250 (along thepivot axis of the hammer element 204) and is cylindrically shaped toprovide a surface on which the coil portion of the hammer biasing member226 bears.

The pivot support insert hole 258 is defined within the biasing membersupport portion 256 and configured to receive the first pivot support212 therein. The first pivot support 212 passes through the pivotsupport insert hole 258 while both ends of the first pivot support 212are supported by the support openings 242A and 242B.

The fixing pin insert hole 260 is configured to receive the first pivotsupport pin 228, which is used to fix the hammer element 204 with thefirst pivot support 212. In the depicted embodiment, the fixing pininsert hole 260 is formed to be perpendicular to the pivot axis A1(i.e., a length of the pivot support insert hole 258) and incommunication with the pivot support insert hole 258. The first pivotsupport pin 228 is configured to be inserted into a fixing pinreceptacle 213 of the first pivot support 212 through the fixing pininsert hole 260. When the first pivot support 212 is inserted to thesupport openings 242A and 242B, the fixing pin receptacle 213 isarranged to be aligned with the fixing pin insert hole 260 so that thefirst pivot support pin 228 is inserted into the fixing pin insert hole260 and the fixing pin receptacle 213. By the first pivot support pin228, the hammer element 204 is fixed to the first pivot support 212 andtherefore can rotate together with the first pivot support 212.

The notch portion 262 is configured to interact with a hammer pad 312(FIG. 8) of the trigger element 208 and provides a secondary safetyfunction. As discussed herein, the notch portion 262 and the hammer pad312 of the trigger element 208 each have opposing surfaces which willpassively come into contact with each other without the trigger 110being pulled rearward. For example, the hammer pad 312 engages the notchportion 262 when the sear mechanism 120 is in the cocked position. Inthe event that the trigger sear 306 fails to engage the hammer sear 266in the cocked position, the interaction of the hammer pad 312 with thenotch portion 262 operates as the secondary safety that can prevent thehammer element 204 from being activated by the hammer biasing member226.

The hammer leg 264 extends from the hammer body 250 and toward thedisconnector element 206 and the trigger element 208. The hammer leg 264is configured to connect the hammer body 250 and the hammer sear 266.

The hammer sear 266 is configured to interact with, and come intocontact with, at least one of the disconnector element 206 and thetrigger element 208 as the hammer element 204 moves from the releasedposition to the cocked position and/or when the hammer element 204 is inthe cocked position. The hammer sear 266 can cooperate with a portion ofthe disconnector element 206 to position the disconnector element 206relative to the trigger element 208 and/or the housing 202, and alsocooperate with a portion of the trigger element 208 to hold the hammerelement 204 in the cocked position and release the hammer element 204from the cocked position.

The first sear edge 268 of the hammer sear 266 is configured toselectively interlock with a trigger sear 306 (FIG. 8) of the triggerelement 208 in the cocked position. In at least one embodiment, thefirst sear edge 268 is formed at an edge of the hammer sear 266 adjacentthe trigger sear 306 of the trigger element 208. The first sear edge 268operates as a hook or flange for selectively engaging the hammer sear266 with the trigger sear 306 of the trigger element 208.

The second sear edge 270 of the hammer sear 266 is configured toselectively interact with a rearward face (i.e., a hammer sear contactface 282 (FIG. 7) of the disconnector element 206 when the searmechanism 120 changes between the cocked position and the releasedposition. In at least one embodiment, the second sear edge 270 is formedat an edge of the hammer sear 266 opposite to the first sear edge 268.The second sear edge 270 operates as a stopping edge or face forcontacting the rearward face of the disconnector element 206.

FIG. 7 is a perspective view of the disconnector element 206 of FIG. 4.The disconnector element 206 extends between a first disconnector end274 and a second disconnector end 276. In at least one embodiment, thedisconnector element 206 includes a pivot support insert hole 278, afixing pin insert hole 280, a hammer sear contact face 282, and atrigger element contact portion 284.

The pivot support insert hole 278 is formed in the body of thedisconnector element 206 between the first and second disconnector ends274 and 276. The pivot support insert hole 278 is configured to receivethe second pivot support 214 therein. The second pivot support 214passes through the pivot support insert hole 278 while both ends of thesecond pivot support 214 are supported by the support openings 244A and244B. As described herein, the disconnector element 206 is at leastpartially placed in a receptacle 298 (FIG. 8) of the trigger element 208such that the pivot support insert hole 278 of the disconnector element206 is aligned with first and second pivot support insert holes 300 and302 of the trigger element 208. Thus, the second pivot support 214 isinserted to the first pivot support insert hole 300 of the triggerelement 208, the pivot support insert hole 278 of the disconnectorelement 206, the second pivot support insert hole 302 of the triggerelement 208 and is rotatably supported by the support openings 244A and244B of the housing 202.

The fixing pin insert hole 280 is configured to receive the second pivotsupport pin 230, which is used to fix the disconnector element 206 withthe second pivot support 214. In the depicted embodiment, the fixing pininsert hole 280 is formed to be perpendicular to a pivot axis A2 (i.e.,the length of the pivot support insert hole 278) and in communicationwith the pivot support insert hole 278. The second pivot support pin 230is configured to be inserted into a fixing pin receptacle 215 of thesecond pivot support 214 through the fixing pin insert hole 280.

The hammer sear contact face 282 is configured to selectively contactthe second sear edge 270 of the hammer sear 266. As described herein,the hammer sear contact face 282 can contact the second sear edge 270 ofthe hammer sear 266 when the hammer element 204 moves between the cockedposition and the released position. In at least one embodiment, thehammer sear contact face 282 is arranged at or proximate to the seconddisconnector end 276.

The trigger element contact portion 284 is arranged at or proximate tothe first disconnector end 274 and configured to selectively contact thehammer tail 254. As described herein, in at least one embodiment, thetrigger element contact portion 284 is configured to selectively engagea disconnector pad 310 (FIG. 8) of the trigger element 208.

FIG. 8 is a perspective view of the trigger element 208 of FIG. 4. Thetrigger element 208 includes and generally extends between a firsttrigger end 290 and a second trigger end 292. In at least oneembodiment, the trigger element 208 includes a base 294, a side wall296, a rod engaging portion 297, a disconnector receptacle 298, a firstpivot support insert hole 300, a second pivot support insert hole 302, abiasing member support 304, a trigger sear 306 having a sear contactsurface 308, a disconnector pad 310, and a hammer pad 312.

The base 294 extends between the first and second trigger ends 290 and292 and is configured to be rotatably connected to the housing 202 androtatably engage the disconnector element 206, as described herein.

The side wall 296 is arranged between the first and second trigger ends290 and 292 and extends from the base 294. In at least one embodiment,the side wall 296 extends vertically from the base 294.

The rod engaging portion 297 is configured to operatively engage an endof the trigger rod 144 opposite to the other end of the trigger rod 144,which engages the trigger 110.

The disconnector receptacle 298 is formed in the base 294 and configuredto at least partially receive the disconnector element 206. Thedisconnector element 206 is pivotally received into the receptacle 298via the second pivot support 214.

The first and second pivot support insert holes 300 and 302 are formedon the opposing sides of the trigger element 208 (e.g., the base 294),respectively, between the first and second trigger ends 290 and 292. Thefirst and second pivot support insert holes 300 and 302 are configuredto receive the second pivot support 214 therein. The first and secondpivot support insert holes 300 and 302 are aligned to the pivot supportinsert hole 278 of the disconnector element 206 when the disconnectorelement 206 is inserted into the disconnector receptacle 298. Then, thesecond pivot support 214 is inserted to the first pivot support inserthole 300, the pivot support insert hole 278 of the disconnector element206, and the second pivot support insert hole 302 in order or viceversa. As described above, the second pivot support 214 is fixedlyconnected to the disconnector element 206 by the second pivot supportpin 230, and the second pivot support 214 is freely rotatable relativeto the trigger element 208 and the housing 202. Thus, the disconnectorelement 206 and the trigger element 208 are supported by the housing 202via the second pivot support 214 and independently rotatable relative tothe housing 202.

The biasing member support 304 is configured to hold one end of thedisconnector biasing member 224 while the other end of the disconnectorbiasing member 224 is supported by the disconnector biasing support 222mounted to the disconnector element 206. The biasing member support 304can be arranged at or adjacent the second trigger end 292 of the triggerelement 208.

The trigger sear 306 is configured to selectively engage or contact thehammer sear 266 as the hammer element 204 moves between the cockedposition and the released position. In at least one embodiment, thetrigger sear 306 is formed on the side wall 296 such that the searcontact surface 308 of the trigger sear 306 is positioned above the base294. As illustrated, in some embodiments, the trigger sear 306 iscantilevered from the side wall 296. An example interaction of thetrigger sear 306 with other components of the sear mechanism 120 isillustrated and described in more detail with reference to FIG. 10.

The sear contact surface 308 of the trigger sear 306 is a surface onwhich the hammer sear 266 of the hammer element 204 slides as the hammerelement 204 moves between the cocked position and the released position.In at least one embodiment, the first sear edge 268 of the hammer sear266 is configured to selectively contact the sear contact surface 308 ofthe trigger sear 306. An example structure and/or manufacturing processof the sear contact surface 308 is illustrated and described in moredetail with reference to FIGS. 14-18.

The disconnector pad 310 provides a surface to which the trigger elementcontact portion 284 of the disconnector element 206 selectivelycontacts, depending on the position of the disconnector element 206relative to the trigger element 208. The disconnector pad 310 isconfigured to position the disconnector element 206 relative to thetrigger element 208. In at least one embodiment, the disconnector pad310 is arranged on the base 294 at or adjacent the first trigger end290. An example structure and manufacturing process of the disconnectorpad 310 is illustrated and described in more detail with reference toFIGS. 14-16 and 19-20.

The hammer pad 312 provides a surface to which the hammer tail 254(e.g., the notch 262 thereof) selectively contacts, depending on theposition of the hammer element 204 relative to the trigger element 208.In at least one embodiment, the hammer pad 312 of the trigger element208 and the notch 262 of the hammer element 204 cooperate to provide asecondary safety mechanism, which operates to prevent accidentaldischarging of the firearm 100 in the event that the firearm 100 isloaded and the hammer element 204 is in the cocked position. Theinteraction of the hammer pad 312 and the notch 262 can catch the hammerelement 204 and prevent the firearm 100 from discharging even if thehammer sear 266 and the trigger sear 306 release the hammer element 204from the cocked position without a trigger pull. An example structureand/or manufacturing process of the hammer pad 312 is illustrated anddescribed in more detail with reference to FIGS. 14-16 and 21-22.

FIG. 9 is a side cross-sectional view of the sear mechanism 120illustrating the assembly of the sear mechanism 120. In FIG. 9, the searmechanism 120 is in the cocked position.

As depicted, the trigger element 208 is rotatably supported by thesecond pivot support 214 within the bore 236 of the housing 202. Thetrigger element 208 is positioned in the housing 202 such that the firsttrigger end 290 and the second trigger end 292 are arranged adjacent thefirst housing end 235 and the second housing end 237, respectively.Therefore, the disconnector pad 310 and the hammer pad 312 are arrangedadjacent the first housing end 235. The trigger element 208 engages thetrigger biasing member 220 against the housing 202 adjacent the firsthousing end 235. The trigger biasing member 220 operates to bias thetrigger element 208 counterclockwise around the second pivot support 214from the view of FIG. 9.

The disconnector element 206 is rotatably supported by the second pivotsupport 214 within the bore 236 of the housing 202. The disconnectorelement 206 is positioned in the housing 202 such that the firstdisconnector end 274 and the second disconnector end 276 are arrangedadjacent the first housing end 235 and the second housing end 237,respectively. As such, the trigger element contact portion 284 isarranged adjacent the first housing end 235, and the hammer sear contactface 282 is arranged adjacent the second housing end 237.

The disconnector biasing member 224 is disposed between the triggerelement 208 and the disconnector element 206 adjacent the second housingend 237. For example, the disconnector biasing member 224 is supportedbetween the second trigger end 292 of the trigger element 208 and thesecond disconnector end 276 of the disconnector element 206. Thedisconnector biasing member 224 operates to bias the disconnectorelement 206 relative to the trigger element 208 and clockwise around thesecond pivot support 214 from the view of FIG. 9. As a result, thedisconnector biasing member 224 causes the trigger element contactportion 284 of the disconnector element 206 to contact the disconnectorpad 310 of the trigger element 208.

The hammer element 204 is at least partially inserted into the bore 236of the housing 202 and rotatably supported by the first pivot support212. The hammer element 204 is positioned in the housing 202 such thatthe hammer tail 254 is arranged adjacent the first housing end 235 andthe hammer head 252 is arranged adjacent the second housing end 237 inthe cocked position. The hammer element 204 remains biased clockwise bythe hammer biasing member 226 (i.e., toward the released position).

The notch portion 262 of the hammer tail 254 can be selectively engagedand in contact with the hammer pad 312 of the trigger element 208. Asdescribed above, the interaction of the notch portion 262 and the hammerpad 312 operates as a secondary safety mechanism while a first safetymechanism, which is provided by the interaction between the hammer sear266 and the trigger sear 306, fails to work as described herein in thecocked position.

As illustrated in FIG. 9, the hammer sear 266 is arranged generallybetween the trigger sear 306 of the trigger element 208 and the hammersear contact surface 282 of the disconnector element 206. As describedherein, depending on the relative positions of the hammer element 204,the disconnector element 206, and the trigger element 208, the hammersear 266 can contact the hammer sear contact surface 282, and/or engagethe trigger sear 306. An example interaction of the hammer element 204,the disconnector element 206, and the trigger element 208 is illustratedand described in more detail with reference to FIGS. 10 and 11.

FIGS. 10A-10D are schematic views to illustrate a firing operation ofthe sear mechanism 120. In particular, FIGS. 10A and 10B illustrate afirst stage trigger operation, and FIGS. 10C and 10D illustrate a secondstage trigger operation.

FIG. 10A depicts that the sear mechanism 120 is completely in the cockedposition. In the cocked position, the hammer sear 266 is fully engagedwith the trigger sear 306. For example, the first sear edge 268 of thehammer sear 266 is hooked to the sear contact surface 308 of the triggersear 306. The hammer sear 266 does not contact the hammer sear contactsurface 282 of the disconnector element 206 in the cocked position. Thetrigger element contact portion 284 of the disconnector element 206remains contact with the disconnector pad 310 of the trigger element 208due to the biasing force of the disconnector biasing member 224. Thehammer tail 254 is maintained to contact the hammer pad 312 of thetrigger element 208 due to the biasing force of the hammer biasingmember 226.

FIG. 10B illustrates that the sear mechanism 120 is in an intermediateposition. As the trigger 110 is pulled, the trigger rod 144 is pulled ina forward direction D_(F) (i.e., toward the trigger 110 or away from thesear mechanism 120), and therefore the trigger element 208 rotates in afirst rotational direction R1 around the pivot axis A2/A3 (clockwise inFIG. 10B). The disconnector element 206 also rotates in the firstrotational direction R1 along with the trigger element 208 by the forceof the disconnector biasing member 224. From the cocked position to theintermediate position, the disconnector element 206 and the triggerelement 208 rotates together by the disconnector biasing member 224.Accordingly, the sear mechanism 120 moves from the cocked position tothe intermediate position.

In the intermediate position, the hammer sear 266 becomes in contactwith the hammer sear contact surface 282 of the disconnector element206. However, the overlap or engagement of the hammer sear 266 with thetrigger sear 306 has been reduced because the trigger element 208 hasshifted in the direction R_(F) relative to the hammer element 204.However, the hammer sear 266 is still engaged with the trigger sear 306so as to be held by the trigger sear 306. The trigger element contactportion 284 of the disconnector element 206 remains contact with thedisconnector pad 310 of the trigger element 208 due to the biasing forceof the disconnector biasing member 224. In at least some embodiment, thehammer tail 254 can lose contact with the hammer pad 312 of the triggerelement 208 as the trigger element 208 rotates away from the hammer tail254.

The sear mechanism 120 is considered to be in the operation of a firststage trigger from the cocked position to the intermediate position. Asthe trigger 110 is pulled, the trigger element 208 and the disconnectorelement 206 rotates together around the second pivot support 214 in thefirst rotational direction R1 while overcoming resistance of the triggerbiasing member 220. The trigger 110 has been pulled until the hammersear 266 has contacted the hammer sear contact surface 282 of thedisconnector element 206. At this point, the overlap of the hammer sear266 with the trigger sear 306 has been reduced. In the intermediateposition, a shooter will fell a distinct stop point where the hammersear 266 is attempting to rotate the disconnector element 206 around thesecond pivot support 214 in a second rotational direction R2 opposite tothe first rotational direction R1. The location of this stop pointcontrols the amount of overlap left on the hammer sear 266 and thetrigger sear 306, and marks the end of the first stage triggeroperation. In at least one embodiment, the disconnector biasing member224 and/or the trigger biasing member 220 can be selected to provide apredetermined amount of force required to pull the trigger 110 in thefirst stage. For example, the disconnector biasing member 224 and/or thetrigger biasing member 220 can be selected to adjust the amount ofresistance against which the trigger element 208 and/or the disconnectorelement 206 rotate from the cocked position to the intermediate positionas the trigger 110 is pulled. In at least one embodiment, thepredetermined amount of force or pressure at the first stage ranges from1.0 lbs to 5.0 lbs. In other embodiments, the predetermined amount offorce or pressure at the first trigger state can be about 2.5 lbs.

FIG. 10C illustrates that the sear mechanism 120 is at a release point.At the release point, the hammer sear 266 is disengaged from the triggersear 306 as the trigger 110 is further pulled from the intermediateposition. Only a slight amount of additional pressure on the trigger 110will further rotate the trigger element 208 in the first rotationaldirection Dl while blocking the disconnector element 206 from rotatingin the first rotational direction Dl. As a result, a gap between thetrigger sear 306 and the hammer sear contact surface 282 becomes largerso that the hammer sear 266 slips off the trigger sear 306, therebyallowing the hammer element 204 to rotate under the force of the hammerbiasing member 226 and strike the firing pin of the bolt assembly 142,discharging the firearm 100, as illustrated in FIG. 10D.

The sear mechanism 120 is in the operation of a second stage trigger asthe slight additional pressure is applied to the trigger 110 from thefirst stage trigger operation. To minimize the amount of the additionalpressure, a minimal amount of overlap between the hammer sear 266 andthe trigger sear 306 is desired. The second stage trigger operationallows the shooter to carefully align his or her sights on target and atthe appropriate moment the slight additional pressure on the trigger 110will allow the firearm 100 to discharge without disturbing the alignmentof the firearm 100 sights. In at least one embodiment, the additionalpressure or force required at the second trigger stage ranges from 1 lbsto 3 lbs. In other embodiments, the additional pressure or force at thesecond trigger stage can be set about 2 lbs.

Further, as in the first trigger stage, the disconnector biasing member224 and/or the trigger biasing member 220 can be selected to adjust theamount of resistance against which the trigger element 208 and/or thedisconnector element 206 rotate in the second trigger stage operation.

FIG. 10D illustrates that the sear mechanism 120 is in the releasedposition. In the released position, the hammer element 204 has rotatedby the force of the hammer biasing member 226 to strike the firing pinof the bolt assembly 142.

FIGS. 11-13 illustrate the trigger element 208 of FIG. 8 again. Inparticular, FIG. 11 is another perspective view of the trigger element208 of FIG. 8. FIG. 12 is a front view of the trigger element 208 ofFIG. 8. FIG. 13 is a rear view of the trigger element 208 of FIG. 8.

As described above, the trigger element 208 includes the trigger sear306 with the sear contact surface 308. In at least one embodiment, thesear contact surface 308 can include a first sear contact surface 320and a second sear contact surface 322. The first and second sear contactsurfaces 320 and 322 provide surfaces on which the first sear edge 268of the hammer sear 266 slides as the hammer element 204 moves betweenthe cocked position and the released position. In at least oneembodiment, the first sear contact surface 320 can adjoin the secondsear contact surface 322 at a predetermined angle ANG. The angle ANGdefined by the first and second sear contact surfaces 320 and 322 canrange between 70 and 110 degrees. In other embodiments, the angle ANG isapproximately 90 degrees.

The trigger element 208 can further include a sear processing aperture324 that is formed on the side wall 296 and designed to be used formachining the sear contact surface 308. In at least one embodiment, thesear processing aperture 324 is configured to engage a wire 446 (FIGS.18, 20 and 22) of electric discharge machining, as described herein. Insome embodiments, the sear processing aperture 324 can be arrangedadjacent an edge of the trigger sear 306 so that the sear contactsurface 308 is processed or machined at the edge of the trigger sear306. As a result of the process or machining of the sear contact surface308, a processing path 326 is formed on the side wall 296 along the searcontact surface 308. In the depicted embodiment, the processing path 326is formed along the first and second sear contact surfaces 320 and 322as the wire of electric discharge machining moves to process the firstand second sear contact surfaces 320 and 322. In other embodiments, thesear processing aperture 324 is positioned away from the trigger sear306 in the trigger element 208. Once the wire 446 is inserted throughthe sear processing aperture 324, the wire 446 in operation can cutthrough the trigger element 208 to reach the trigger sear 306 whileforming a path connecting the sear processing aperture 324 and thetrigger sear 306. Then, the wire 446 continuously forms the processingpath 326 as it processes the first and second sear contact surfaces 320and 322.

As described above, the trigger element 208 includes the disconnectorpad 310. The disconnector pad 310 provides a disconnector contactsurface 330 with which the trigger element contact portion 284 isselectively in contact. The disconnector pad 310 has a predeterminedheight from the base 294 of the trigger element 208 to determine theposition of the disconnector element 206 relative to the trigger element208. The accurate dimension (e.g., height) and smoothness of thedisconnector pad 310 is critical to control the interaction between thehammer element 204, the disconnector element 206, and the triggerelement 208, thereby the performance of the two-stage trigger operationof the sear mechanism 120.

The trigger element 208 can further include a disconnector padprocessing aperture 332 that is formed on the side wall 296 and designedto be used for machining the disconnector contact surface 330. Thedisconnector pad processing aperture 332 can be arranged adjacent thedisconnector pad 310 so that the disconnector contact surface 330 ismachined on the disconnector pad 310. In other embodiments where theside wall 296 does not extend adjacent the disconnector pad 310, thetrigger element 208 does not need the disconnector pad processingaperture 332 to machine the disconnector contact surface 330.

As described above, the trigger element 208 includes the hammer pad 312.The hammer pad 312 provides a hammer contact surface 334 on which thehammer tail 254 (e.g., the notch 262) slides. The hammer pad 312 has apredetermined height from the base 294 of the trigger element 208 todetermine the position of the hammer element 204 relative to the triggerelement 208. Similarly to the disconnector pad 310, the accuratedimension (e.g., height) and smoothness of the hammer pad 312 iscritical to control the interaction between the hammer element 204, thedisconnector element 206, and the trigger element 208, thereby theperformance of the two-stage trigger operation of the sear mechanism120.

FIG. 14 illustrates an example method 400 of manufacturing the triggerelement 208. In at least one embodiment, the method 400 includesoperations 402 and 404. At the operation 402, an intermediate workpiece408 (FIG. 15) for the trigger element 208 is produced. The intermediateworkpiece 408 can be produced in various manufacturing processes. Insome embodiment, the intermediate workpiece 408 is produced by casting.Casting is a manufacturing process by which a liquid material is pouredinto a mold. The mold is designed to contain a hollow cavity of theshape of the intermediate workpiece 408. Once the material is solidifiedin the mold, the casted product (i.e., the intermediate workpiece 408)is ejected out of the mold. In other embodiments, the intermediateworkpiece 408 is manufactured by other processes, such as forging andmachining.

At the operation 404, electric discharge machining (EDM) is performed onthe intermediate workpiece 408 to produce the end product of the triggerelement 208. In at least one embodiment, EDM is used to provide at leastone contact surface onto which at least one pivotable or movable element(e.g., the hammer element 204 and/or the disconnector element 206) ofthe sear mechanism selectively contacts and/or slides. EDM is amanufacturing process by which a desired shape is obtained usingelectrical discharges or sparks. In at least one embodiment, the EDM canuse two electrodes that are separated by a dielectric liquid and subjectto an electric voltage. A series of rapidly recurring current dischargesbetween the electrodes operates to remove at least some of the materialsof a workpiece. In other embodiments, wire electrical dischargemachining (WEDM) can be used to machine the intermediate workpiece 408to produce the trigger element 208. The WEDM can typically use a thinsingle-strand metal wire 446, such as a brace wire, that is fed througha workpiece while the workpiece is submerged in a tank of dielectricfluid, such as deionized water.

As described herein, the EDM can be used primarily to create the searcontact surface 308, the disconnector contact surface 330, and thehammer contact surface 334.

FIGS. 15A and 15B illustrate an example intermediate workpiece 408 forthe trigger element 208. In particular, FIG. 15A is a side view of anexample intermediate workpiece 408, and FIG. 15B is a perspective viewof the intermediate workpiece 408 of FIG. 15A.

As described in FIG. 14, the intermediate workpiece 408 can be producedby a manufacturing process, such as casting, forging, or machining. Theintermediate workpiece 408 can include one or more unfinished portionsthat are to be machined in subsequent processes, such as the operation402 in FIG. 14. In the illustrated example, the intermediate workpiece408 does not have the sear contact surface 308 at the trigger sear 306,the disconnector contact surface 330 on the disconnector pad 310, andthe hammer contact surface 334 on the hammer pad 312.

FIG. 16 illustrates an example method 420 of performing the operation404 of FIG. 14. In at least one embodiment, the method 420 includesoperations 422, 424 and 426.

The method 420 is designed to machine the sear contact surface 308, thedisconnector contact surface 330, and the hammer contact surface 334 toproduce the trigger element 208.

At the operation 422, the cantilever trigger sear 306 is processed tocreate the sear contact surface 308. In at least one embodiment, EDM canbe performed to provide the sear contact surface 308 at one end of thetrigger sear 306.

At the operation 424, the disconnector pad 310 is processed to createthe disconnector contact surface 330. In at least one embodiment, EDMcan be performed to provide the disconnector contact surface 330 on thedisconnector pad 310.

At the operation 426, the hammer pad 312 is processed to create thehammer contact surface 334. In at least one embodiment, EDM can beperformed to provide the hammer contact surface 334 on the hammer pad312.

In other embodiments, the method 420 can perform the operations 422, 424and 426 in different order. The method 420 can also omit one or more ofthe operations 422, 424 and 426, or perform at least one of theoperations 422, 424 and 426 with other operations.

FIG. 17 illustrates an example method 430 of performing the operation422 of FIG. 16. In at least one embodiment, the method 430 includesoperations 432 and 434.

The method 430 involves using wire electrical discharge machining (WEDM)to produce the sear contact surface 308. WEDM can use a metal wire 446(FIG. 18) that is engaged through the intermediate workpiece 408 tocreate sparks between the metal wire 446 and a portion of the workpiece408 abutting the wire 446 while the intermediate workpiece 408 issubmerged in a tank of dielectric fluid. The sparks can cut the surfaceof the workpiece to form a desired shape.

At the operation 432, the wire 446 is engaged through the searprocessing aperture 324 of the intermediate workpiece 408. Theintermediate workpiece 408 can be submerged in a dielectric fluid andguided by a clamping device or work table.

At the operation 434, either the intermediate workpiece 408 or the wire466 is moved relative to each other as necessary to form the searcontact surface 308. In the depicted embodiment, the intermediateworkpiece 408 is continuously shifted in two different directions tocreate the first and second sear contact surfaces 320 and 322. In otherembodiments, the worktable can be shifted to move the wire 466 relativeto the intermediate workpiece 408 to create the sear contact surfaces320 and 322. As the intermediate workpiece 408 is displaced to createthe first and second sear contact surfaces 320 and 322, the processingpath 326 is created along the first and second sear contact surfaces 320and 322.

FIG. 18 schematically illustrates the method 430 of FIG. 17. Asillustrated, the wire 446 used in WEDM is engaged through the searprocessing aperture 324. The intermediate workpiece 408 can be movedrelative to the wire 446 in different directions (or vice versa) so thatthe sear contact surface 308 is created. Electric current flowingthrough the wire 446 subject to a predetermined voltage will causesparks when the wire 446 abuts the trigger sear 306 and produce the searcontact surface 308 on the trigger sear 306.

FIG. 19 illustrates an example method 450 of performing the operation424 of FIG. 16. In at least one embodiment, the method 450 includesoperations 452 and 454.

At the operation 452, the wire 446 is engaged through the disconnectorpad processing aperture 332 of the intermediate workpiece 408. Theintermediate workpiece 408 can be submerged in a dielectric fluid andguided by a clamping device or work table.

At the operation 454, either the intermediate workpiece 408 or the wire446 is moved as necessary to form the disconnector contact surface 330.In the depicted embodiment, the intermediate workpiece 408 iscontinuously shifted in two different directions to create thedisconnector contact surface 330 on the disconnector pad 310. In otherembodiments, the worktable can be shifted to move the wire 466 relativeto the intermediate workpiece 408 to create the disconnector contactsurface 330 on the disconnector pad 310.

FIG. 20 schematically illustrates the method 450 of FIG. 19. Asillustrated, the wire 446 used in WEDM is engaged through thedisconnector pad processing aperture 332. The intermediate workpiece 408can be moved relative to the wire 446 in different directions (or viceversa) so that the disconnector contact surface 330 is created on thedisconnector pad 310. Electric current flowing through the wire 446subject to a predetermined voltage will cause sparks when the wire 446abuts the disconnector pad 310 and produce the disconnector contactsurface 330 thereon.

In at least one embodiments, the disconnector pad 310 is provided on thebase 294 such that a width D_(P1) of the disconnector pad 310 (inparticular, a width of the disconnector contact surface 330) in thedirection of the wire 446 is smaller than a width D_(W) of the base 294in the same direction. In some embodiments, the width D_(P1) of thedisconnector pad 310 is in a range from 0.1 to 0.9 times the width D_(W)of the base 294. In other embodiments, the width D_(P1) of thedisconnector pad 310 is in a range from 0.2 to 0.6 times the width D_(W)of the base 294. In yet other embodiments, the width D_(P1) of thedisconnector pad 310 is in a range from 0.3 to 0.4 times the width D_(W)of the base 294. The disconnector pad 310 smaller than the base 294 inthe direction along the wire 446 helps reducing a manufacturing time andincreasing productivity of the EDM process. The principle of making thewidth D_(P1) of the disconnector pad 310 smaller than the width D_(W) ofthe base 294 can be used in various trigger designs other than thedisconnector pad 310 of the trigger element 208 to achieve the decreasedmanufacturing time and increased productivity.

FIG. 21 illustrates an example method 470 of performing the operation426 of FIG. 16. In at least one embodiment, the method 470 includesoperations 472 and 474.

At the operation 472, the wire 446 is arranged adjacent the hammer pad312 of the intermediate workpiece 408. The intermediate workpiece 408can be submerged in a dielectric fluid and guided by a clamping deviceor work table.

At the operation 474, either the intermediate workpiece 408 or the wire446 is moved as necessary to form the hammer contact surface 334. In thedepicted embodiment, the intermediate workpiece 408 is continuouslyshifted in two different directions to create the hammer contact surface334 on the hammer pad 312. In other embodiments, the worktable can beshifted to move the wire 466 relative to the intermediate workpiece 408to create the hammer contact surface 334 on the hammer pad 312.

FIG. 22 schematically illustrates the method 470 of FIG. 20. Asillustrated, the wire 446 used in WEDM is arranged adjacent the hammerpad 312 so that the wire 446 substantially contacts the hammer pad 312.The intermediate workpiece 408 can be moved relative to the wire 446 indifferent directions (or vice versa) so that the hammer contact surface334 is created on the hammer pad 312. Electric current flowing throughthe wire 446 subject to a predetermined voltage will cause sparks whenthe wire 446 abuts the hammer pad 312 and produce the hammer contactsurface 334 thereon.

In at least some embodiments, the hammer pad 312 is provided on the base294 such that a width D_(P2) of the hammer pad 312 (in particular, awidth of the hammer contact surface 334) in the direction of the wire446 is smaller than the width D_(W) of the base 294 in the samedirection. In some embodiments, the width D_(P2) of the hammer pad 312is in a range from 0.1 to 0.9 times the width D_(W) of the base 294. Inother embodiments, the width D_(P2) of the hammer pad 312 is in a rangefrom 0.3 to 0.8 times the width D_(W) of the base 294. In yet otherembodiments, the width D_(P2) of the hammer pad 312 is in a range from0.5 to 0.7 times the width D_(W) of the base 294. The hammer pad 312smaller than the base 294 in the direction along the wire 446 helpsreducing a manufacturing time and increasing productivity of the EDMprocess. The principle of making the width D_(P1) of the hammer pad 312smaller than the width D_(W) of the base 294 can be used in varioustrigger designs other than the hammer pad 312 of the trigger element 208to achieve the decreased manufacturing time and increased productivity.

The various examples described above are provided by way of illustrationonly and should not be construed to limit the scope of the presentdisclosure. Those skilled in the art will readily recognize variousmodifications and changes that may be made without following the exampleexamples and applications illustrated and described herein, and withoutdeparting from the true spirit and scope of the present disclosure.

What is claimed is:
 1. A method for manufacturing a trigger element of a sear mechanism for a firearm, the method comprising: producing an intermediate workpiece of the trigger element by a manufacturing process; and electric discharge machining the intermediate workpiece of the trigger element to provide at least one contact surface onto which at least one pivotable element of the sear mechanism selectively contacts.
 2. The method of claim 1, wherein the intermediate workpiece includes a trigger sear configured to selectively engage a hammer sear of a hammer element of the sear mechanism; and wherein electric discharge machining the intermediate workpiece of the trigger element includes electric discharge machining the trigger sear to provide a sear contact surface onto which the hammer sear slides.
 3. The method of claim 2, wherein the trigger sear is cantilevered from a side wall of the trigger element.
 4. The method of claim 2, wherein electric discharge machining the trigger sear comprises: engaging a metal wire through a sear processing aperture of the intermediate workpiece; and moving the intermediate workpiece or the wire relative to each other to form the sear contact surface.
 5. The method of claim 2, wherein the sear contact surface includes a first sear contact surface and a second sear contact surface adjoining the first sear contact surface at a predetermined angle.
 6. The method of claim 5, wherein the angle ranges between 70 and 100 degrees.
 7. The method of claim 5, wherein the angle is 90 degrees.
 8. The method of claim 1, wherein electric discharge machining the intermediate workpiece of the trigger element includes electric discharge machining a hammer pad to provide a hammer contact surface onto which a hammer tail of the hammer element slides, the hammer pad configured to selectively engage the hammer tail of the hammer element.
 9. The method of claim 8, wherein electric discharge machining a hammer pad comprises: arranging a metal wire adjacent the hammer pad of the intermediate workpiece; and moving the intermediate workpiece or the wire relative to each other to form the hammer contact surface.
 10. The method of claim 1, wherein electric discharge machining the intermediate workpiece of the trigger element includes electric discharge machining a disconnector pad to provide a disconnector contact surface to which a disconnector element of the sear mechanism contacts, the disconnector pad configured to selectively engage the disconnector element.
 11. The method of claim 10, wherein electric discharge machining a disconnector pad comprises: engaging a metal wire through a disconnector pad processing aperture of the intermediate workpiece; and moving the intermediate workpiece or the wire relative to each other to form the disconnetor contact surface. 